Abstract ? Overall Component This application seeks P2C continuation funding for the Columbia Population Research Center (CPRC), co- directed by Jennifer S. Hirsch, Professor of Sociomedical Sciences at the Mailman School of Public Health, and Jane Waldfogel, Compton Foundation Centennial Professor for the Prevention of Children's and Youth Problems at the Columbia University School of Social Work. CPRC's mission is to increase the scientific impact, innovation, and productivity of population researchers at Columbia, increase their competitiveness for peer- reviewed external funding in population dynamics research, help junior population scientists achieve research independence, and maximize the efficiency of funding for population dynamics research. To achieve that mission, our specific aims are to: (1) nourish a vibrant cross-campus intellectual community of population researchers at Columbia, fostering the development of junior population scientists and encouraging collaborations among population scientists and between population scientists and scientists in other disciplines; (2) advance population research in CPRC's four primary research areas (PRAs): children, youth, and families; reproductive health and HIV; immigration/migration; and urbanism; (3) continue to be a leading population center focused on research on inequalities in the health and well-being of vulnerable populations, and on public policies relevant to those populations; and (4) take advantage of Columbia's location in New York City by partnering with city policy makers and practitioners to address mutual research interests. The coordinated work of three research infrastructure cores?administrative, computing and methods, and development?will facilitate cross-disciplinary and cross-campus population dynamics research at Columbia, with a particular focus on advancing the professional development of junior scientists. Signature strengths of CPRC are the integration of researchers across three schools (Social Work, Public Health, and Arts and Sciences); a new emphasis on the cross-cutting themes of inequality and the impact of public policies on well-being; the diversity of our faculty at both the junior and senior scientist level; the crucial role of the center in transforming computing infrastructure for population research at the university; and the substantial leveraging of university support, with an institutional commitment of two times the total requested NICHD budget. Another signal strength of CPRC are the six vibrant cross-campus working groups, which complement the work of the PRAs by bringing together scientists from across the campus with shared interests in autism spectrum disorders, justice and incarceration, the Fragile Families data, policy and population health dimensions of the opioid epidemic, the environment, climate change, and population health, and housing and neighborhoods. These vibrant working groups, the PRAs, and the other structures and services provided by CPRC demonstrate that the center has successfully created and sustained a robust population science research community that spans disciplinary, geographic, and administrative borders at Columbia.